Here's the situation: I'm building a new system and pulling the good parts off of my old one. My power demands could be considerable. My old PSU is a Corsair HX620. I'm planning on running a Q9550 on a P45 board, a single 4870 x2 (new), 8gb of high end DDR2 ram (Vista 64), 6 hard drives (4tb) from the old box, plus the misc other items (fans, rom drives etc).

I wasn't too concerned about it until I read the ATI spec on the 4870x2 that said I would need a minimum supply of 650W.

My new case will support (has space) for 2 PSUs. If the HX620 won't easily handle the load, would it be feasible to add a second PSU that could be dedicated to select components. Or would it make more sense to use a single Large(er) PSU?

Aside from dual components added heat and potential noise, what would the pros/cons be for each option? What would happen to the system if one of the PSUs failed?

__________________"The bus station is where the bus stops. The train station is where the train stops. On my desk, I have a workstation..." -- Steven Wright

You won't have added heat because one PSU @ 80% efficiency putting out 500W is giving off 100W of heat. Two PSU's @ 80% efficiency putting out about 250W each is giving off 50W of heat each.

But I can imagine funky things happening if one PSU were to stop working. I guess you should make sure one PSU powers just the graphics cards because if you lose power on those connectors, you'll know without damaging anything. Not sure how you'll handle the minimum load requirements of the other rails though. Resistors?

HOOfan,
Sorry to disappoint, but I'm actually a Florida Gator (no cracks about last Saturday, please ;-). The Wahoo comes from a surf club a buddy and I started, in Jacksonville, years ago.

I will say that I can certainly appreciate UVA's rep for students with larger than normal medulla oblongatas
What I'm gathering from this short thread is that I will most likely avoid a huge headache by simply upgrading to a single, larger PSU.